1. Field of the Invention
The present invention relates generally to a photographic camera with shock stabilizing means, and more particularly, to a pair of juxtaposed processing members positioned at a predetermined location in a shock stabilizing mounting within the camera for optimizing the processing of an exposed self-developing type film unit.
2. Description of the Prior Art
An important step in the processing of a self-developing type film unit having a photosensitive element is the distribution of a fluid processing composition between a predetermined pair of layers of the film unit, subsequent to exposure, to initiate a development and diffusion transfer process. In order to optimize the process, the processing composition must be uniformly distributed over an entire exposed area of the photosensitive element.
In a typical "peel apart" arrangement, a sheet of photosensitive material is first exposed to form a latent image therein and is subsequently progressively pressed against an image-receiving sheet with a predetermined quantity of processing fluid being disposed therebetween. The fluid may initially be releasably stored in a rupturable pod attached to a leading end of one of the sheets. As the film unit comprising the sheets and the pod is advanced leading end first between a pair of processing members, a compressive force is exerted upon the film unit which first ruptures the pod and subsequently spreads the processing fluid in a layer between the superposed sheets as is fully described in U.S. Pat. No. 3,080,805 entitled "Photographic Apparatus" issued on Mar. 12, 1963 to Joel A. Hamilton and assigned in common herewith. The processing members used therewith may typically comprise either a pair of juxtaposed pressure rollers, one roller and a stationary member, or a pair of rigid stationary members.
The photographic diffusion transfer process involved is an exceedingly delicate one, particularly when the process is one producing an image in full color. The mounting of the processing apparatus within the camera may well provide the difference between an image which is defective as, for example in its color properties, and one which is entirely satisfactory. Therefore, it is to be emphasized that the processing apparatus and a mounting arrangement therefor is critical to the photographic development of a satisfactory photographic print produced by a self-developing photographic camera.
Traditionally, in commercially available systems, the processing apparatus are manually operated. A leader attached to the film unit is pulled from within the camera to one side of the pressure-applying members thereby drawing a leading end of the film unit between the pressure-applying members whereby the leading end of the film unit may be grasped and the film unit withdrawn from within the camera between the pressure-applying members through a film exit slot included in a door pivotally attached to the body of the camera. A typical processing apparatus developed for use with a self-developing film of this type is fully described in U.S. Pat. No. 3,165,039 entitled "Photographic Apparatus" issued on Jan. 12, 1965 to Roger B. Downey and assigned in common herewith. The processing apparatus disclosed therein is principally mounted and fixedly secured to the pivotally mounted door attached to the body of the camera. The processing apparatus through the instrumentality of an intermediate mounting plate is secured to the pivotally mounted door. A support frame formed from a rigid metal serves as a basic support for a pair of juxtaposed pressure rollers. The support frame is permanently attached to the mounting plate by a pair of rivets whereby the entire support frame including the pressure rollers may be pivotally moved or raised to a non-operative position and lowered into an operative position as a unit with respect to the mounting plate for cleaning. The support frame is generally retained in the operative position against the mounting plate with the pressure rollers held in the operative position by a spring clip. Furthermore, the side walls of the support frame are secured to the mounting plate when the photographic camera is assembled at the factory whereby the relative position of the pressure members in the operative position is permanently established.
An improved processing apparatus is fully described in U.S. Pat. No. 3,745,904 entitled "Low-Cost Roller Type Photographic Fluid Spreading Apparatus" issued on July 17, 1973 to Herbert A. Bing et al. The processing apparatus disclosed therein is adapted to be inserted into and removed from the camera as an integral assembly. The processing apparatus comprises a pair of juxtaposed pressure rollers, bearing blocks and spring elements mounted upon a platform including a spring latch for releasably retaining the processing apparatus in the camera. The spring latch cooperates with a brace provided therefor upon an inner surface of a rear body member of the camera whereby the latch and brace cooperate to snap-fit and retain the processing apparatus in position upon the inner surface of the rear body member. The rear body member includes a film exit slot disposed transversely in a forward wall thereof for manually withdrawing the film units therethrough subsequent to its passage between the pair of juxtaposed pressure rollers or the processing members. The processing apparatus is positioned upon the rear body member such that the pressure rollers are adjacent to the film exit slot and the bite line between the pressure rollers is in alignment with the film exit slot whereby the film unit emerges from between the rollers in a natural or normal emerging path of travel through the film exit to the exterior of the photographic camera.
The mounting apparatus for the processing members including the latch and brace are specifically developed to provide a processing apparatus which may be rapidly and easily attached and removed from its mounted position upon the rear body member to facilitate the cleaning, repair or replacement of parts thereof. While improving the prior art through the ease in which the processing apparatus may be attached and detached from the camera and further lending itself to high volume fabrication and assembly, the processing apparatus relies upon the brace to urge a leading upright edge of the platform firmly against the forward wall of the rear body member and thereby maintain its position upon the rear body member in alignment with and adjacent to the film exit slot in the forward wall.
In the aforementioned processing apparatus, the ultimate goal was to provide an effective distribution of the processing composition contained in the pod without requiring a substantially high pull force to advance the film unit subsequent to exposure between the processing members. The processing apparatus were generally developed along the lines of augmenting the ability of a user to manually withdraw the film unit between the pressure rollers to the exterior of the camera. The mounting arrangements provided therefor positioned the processing members adjacent and in alignment with the film exit slot to substantially prevent the user from mistracking during the withdrawal of the film unit between the pressure members which may lead to insufficient coverage or light spreading of the processing composition across the image area of the photosensitive sheet of the film unit and thereby an unsatisfactory processing and development of the film unit.
Each "peel apart" film unit is provided with a photosensitive sheet which is exposed and a second or print-receiving sheet which remains superposed to the exposed photosensitive sheet during processing. Both of these sheets comprise a support which is opaque to light actinic to the photosensitive material of the photosensitive sheet thereby providing a dark chamber outside of the camera for developing the image. When the film unit is withdrawn from the camera and the processing members have distributed the released processing fluid contained in the pod in a layer between the photosensitive and print-receiving sheets, the photosensitive surface of the photosensitive sheet is protected from surrounding ambient light for a predetermined development period under the control of the user and the photosensitive and the print receiving sheets may be "peeled apart" manually by the user to present a fully developed photographic print.
Recently disclosed highly automatic self-developing cameras include processing members coupled by a gear train to a motor for processing and automatically advancing the film unit to the exterior of the photographic camera. Representative examples of the highly automated self-developing cameras are fully described in U.S. Pat. No. 3,714,879 entitled "Reflex Camera" issued on Feb. 6, 1973 to Edwin H. Land et al. and copending application Ser. No. 554,777 entitled "Photographic Apparatus With Sequencing System" filed Mar. 3, 1975 by Bruce K. Johnson et al. and assigned in common herewith. The photographic cameras are designed for use with a film pack comprising an exclosure or cassette containing "non-peel apart" self-developing type film units which may be integrated with a power supply system for operating electrically controlled mechanism included within the photographic camera. Representative examples of the integral "non-peel apart" self-developing film units are fully described in U.S. Pat. Nos. 3,415,644 entitled "Novel Photographic Products and Processes" issued on Mar. 10, 1967 to Edwin H. Land; and 3,594,165 entitled "Novel Photographic Products and Processes" issued on July 20, 1971 to Howard G. Rogers and assigned in common herewith. Basically, these integral film units are multilayer structures having a fluid processing composition including an opacifying constituent releasably stored in a rupturable pod or container at a leading end and a trap for collecting any excess fluid at a trailing end thereof. The multilayer structure of the film unit includes a pair of outer sheets which are bound together along lateral edges to cooperate with the trap to prevent the fluid processing composition from escaping from between a predetermined pair of layers during the processing operation.
The processing apparatus includes a pair of juxtaposed processing members or pressure rollers. During exposure operations image carrying light rays passing through a lens of the camera are directed onto a transparent surface layer of the film unit before impinging upon a photosensitive system of the film unit. A film advancing mechanism driven by a battery-operated motor which also drives at least one of the processing members serves to advance the film unit to the exterior of the camera subsequent to exposure. The film advancing mechanism removes the exposed film unit from within the cassette and advances the leading edge of the film unit in the direction of the entrance side of the processing members whereby the film unit passes between the pressure members which apply pressure thereto to rupture the pod and progressively distribute a mass of the processing composition intermediate the transparent element and the photosensitive system of the film unit. After passing therebetween, the film unit is released on the exit side of the processing members. Those portions of the film unit progressively exposed to ambient light beyond the exit side of the processing members have already been treated by the processing composition and the opacifying constituent which substantially precludes any ambient light incident upon the transparent layer from reaching adjacent sections of the photosensitive system.
One of the major considerations in developing camera systems for use with film units of this type is to protect non-processed portions of the photosensitive system of the film unit from ambient light. Such light rays can cause undesirable "fogging" or those yet untreated sections of the film unit's photosensitive system. While ambient light incident upon the transparent element of the treated section of the exit side of the processing apparatus cannot pass through the layer of processing composition to adjacent portions of the exposed photosensitive system, a portion of the light rays may be reflected internally of the light transparent element and scatter or diffuse lengthwise therealong until it reaches a position within the light transparent element in advance of the processing composition being spread intermediate the film unit's transparent element and the photosenstive system.
Therefore, in photographic cameras designed for use with film units of the type disclosed in the aforementioned U.S. Pat. Nos. 3,415,644 and 3,594,165, the mounting arrangement for the processing apparatus positions the processing members substantially within the housing of the camera and in direct contrast with the previously described mounting arrangements a predetermined distance away from the forward wall having the film exit slot transversely disposed therein to provide a dark chamber intermediate the exit side of the processing members and the film exit slot in the housing to prevent the film unit from emerging from between the processing members directly into the ambient light. As the film unit emerges from between the processing members on the exit side thereof and prior to its exit from the camera structure through the film exit slot, the portion of the processed film unit treated with the processing composition having the opacifying constituent included therein is shielded from ambient light by the dark chamber.
In direct contrast with the aforementioned manually operated processing apparatus, the film exit slot is displaced substantially below and out of alignment with the bite line between the processing members and thereby out of a natural planar path of travel of the film unit as it emerges from the exit side of the processing members. The length of travel of the film unit within the dark chamber as it emerges from the exit side of the processing member is substantially increased thereby substantially eliminating any adverse effect upon the film unit by ambient light which may penetrate through the film exit slot.
Because the lateral edges of the film unit are bound together, there is more resistance to the flow of the fluid processing composition adjacent to these edges than in a center portion of the film unit as the film unit passes between the rollers. The mass of fluid processing composition discharged by the pod tends to advance rearwardly between the layers of the film unit in a wave front having a greater concentration of fluid in the center than out at the lateral edges of the film unit. Also, the film unit has an inherent stiffness and as the film unit progressively emerges from the processing members into the dark chamber in a cantilever fashion it tends to follow the natural and substantially planar path of travel. A specially configured member extending from the forward wall of the camera's housing rearwardly in the direction of the processing member serves to engage the film unit as it emerges from between the rollers and to deflect it towards the film exit slot. In doing so, the specially configured member urges portions of the film unit still disposed on the entrance side of the processing members against the wave of fluid processing composition advancing rearwardly in the direction of the trailing end of the film unit between adjacent layers or elements thereof. As a result, the movement of the mass of processing composition is substantially controlled by decreasing the amount of processing composition in the center and providing uniformity in the amount of processing composition spread between the layers or elements of the film unit which would not be the case if the natural path of the film unit was left undisturbed as it emerged from the exit side of the processing members.
A self-developing camera having a motor driven spread system structure for inducing a bend in the film unit as it emerges from between the pressure-applying members is fully described in U.S. Pat. No. 3,810,211 issued on May 7, 1974 to R. Paglia et al., and assigned in common herewith. The camera is a compact, folding, single lens reflex type and includes a housing section which extends forwardly of a pair of juxtaposed pressure-applying members. The housing section includes a film exit slot therein which is substantially out of alignment with the natural or normal emerging path of travel of the film unit. A deflecting plate is dispersed in the emerging path of travel of the film unit for deflecting the emerging film unit inducing a beneficial bend or curvature thereto whereby the movement of the mass of processing composition is controlled and the film unit is guided into the film exit slot. The pressure-applying members are separated from the exit slot and the mounting apparatus therefor secures the pressure-applying members in a precise predetermined location within the housing in a fixed operative relationship with the deflecting plate and exit slot which is critical to the distribution of the fluid processing composition within the element.
In the camera described in U.S. Pat. No. 3,810,211, the bite line of the pressure-applying members is critical in determining the distribution of the processing composition and is a major concern in precisely positioning and securing the processing members in operative relationship with the deflecting plate and the film exit slot. A slight misalignment of the processing members which can develop from an extraneous vibration, sudden shock or jarring thereto can lead to incomplete spreading of the processing composition due to heavy concentrations of the processing composition early in the process and may lead to lean spreads resulting in leakage of the processing composition from the trap if the trap fails to contain sufficient volume for receiving the excess processing composition and may result in undesirable low quality photographic prints. For example, the processing apparatus designed for use in such cameras is engineered to provide a coating between the layers of the film unit having a tolerance of .+-.0.0002 inch of the nominal coating thickness. A coating exceeding the upper limit contributes to an incomplete spreading and any value below the lower limit leans towards leakage of the processing composition and photographic prints having a red tint.
The mounting apparatus used to secure the processing members in such cameras within the housing includes metal fasteners for fixedly securing the processing apparatus upon the inner base surface of the housing. A torsion spring is coupled to each end of a bottom pressure roller to bias it in the direction of an upper pressure roller of the processing apparatus. Precision piece parts requiring multiple adjustments are characteristics for the mounting of the processing members at their predetermined location in operative relationship with the deflecting plate and the film exit slot which greatly increases the cost of each piece part and additionally requires special fixing tools and costly man hours to assemble and repair the processing apparatus which is not conducive to providing a low cost camera for the mass amateur market. Furthermore, should the photographic camera be subjected to a sudden severe shock or jarring, the processing members may be dislodged from their previously established critical predetermined location enough to hinder their cricical operative relationship with the deflecting plate and the film exit slot.
Copending application Ser. No. 554,780 entitled "Self-Developing Camera with Film Unit Deflecting Structure", now U.S. Pat. No. 3,994,002, filed on Mar. 3, 1975 by Andrew S. Ivester and assigned in common herewith fully describes a new type of self-developing camera having a housing including a film exit slot and an integrally molded camming member for deflecting the film unit towards the exit slot as it emerges from between the processing members for influencing the distribution of the fluid processing composition being spread between the layers of the film unit. A mounting apparatus for the processing apparatus is fully described in a U.S. Pat. No. 3,974,510 entitled "A Mounting Apparatus For A Spread Roller Assembly" issued to Andrew S. Ivester on Aug. 10, 1976 and assigned in common herewith. The mounting apparatus comprises a bracket for rotatably mounting a pair of juxtaposed pressure-applying members thereon and structure which cooperates with integrally molded structure formed upon an inner surface of a housing section to releasably couple the bracket thereto at a predetermined location therein. The housing section integrally includes a film exit slot transversely disposed therein and a camming member extending rearwardly from a forward wall of the housing section in the direction of the exit side of the processing members for deflecting the film unit as it emerges from between the processing members which serves to influence the distribution of the processing cooperation and to guide the film unit through the film exit slot to the exterior of the camera.
The photographic camera includes a film cassette receiving chamber for slidably receiving a film cassette having a plurality of unexposed film units therein. The bracket is pivotally coupled to a frame located near the entrance to the receiving chamber so that the processing apparatus including the processing members is aligned in operative relationship with an inserted film cassette. The integrally molded structure of the housing section provides a snap fit mounting for the bracket whereby the pressure rollers are releasably retained at the predetermined location therein with the processing members located substantially above the film exit slot and the camming member disposed in the emerging path of travel of the film unit as it is released from between the processing members on the exit side thereof.
The snap fit mounting arrangement provides a snug fit between the processing apparatus and the housing section which substantially prevents lateral, rotational and longitudinal movement therein. The processing apparatus is rigidly held to maintain its predetermined location therein whereby the processing members are retained in operative relationship with the film cassette supported in the receiving chamber of the receiving side and with the camming member and thereby the film exit slot on the exit side of the processing members. Furthermore, the housing section forms the forwardmost section of the camera's housing, that is to say, the remainder of the camera, the lens, film receiving chamber, electrical system etc. are positioned within a main housing of the camera rearwardly thereof which is connected to the housing section by the processing apparatus. In an assembled relatively light weight camera having a total weight of approximately one pound, the processing apparatus contributes substantially to the mass of the camera. The processing apparatus being positioned substantially forward and below the center of gravity of the camera tends to throw the camera out of balance and to make the camera "nose heavy". A carrying strap designed for use in transporting the camera is attached to a rear wall of the main housing of the camera whereby the camera is carried about with the forward wall of the housing section pointed towards the ground. Therefore the camera is generally carried in a normal swinging motion and should the camera be accidentally jarred or inadvertently dropped, the housing section having the processing apparatus rigidly supported therein generally strikes the ground first subjecting the camera to sudden and severe shock which is transmitted directly to the mounting bracket and the critically located processing members. It has been discovered that the kinetic energy received thereby from the impact is imparted through the housing section to the processing apparatus and can lead to substantial damage and severely disrupt the critical relationship between the processing members and the film cassette on the entrance side thereof and the processing members, the camming member and film exit slot on the exit side thereof. In addition thereto, the rigid, snap fit mounting of the mounting bracket within the integrally molded structure of the housing section may, due to conflicting manufacturing tolerances between the mating parts, set up stresses in the mounting bracket whereby the mounting bracket is provided with a backlash reaction to location of the bracket within the housing section thereby initially effecting the critical location of the processing members therein.
From the foregoing, it can be seen that there is a need for a shock stabilizing mounting arrangement for a processing apparatus which includes a shock damping effect to deter accidental damage and dislodgment of the processing apparatus releasably mounted and retained as an integral assembly at a predetermined, critical location upon an inner surface of a housing section and which substantially eliminates backlash reaction to location during the attachment of the processing apparatus to the housing.